METHOD FOR DRY-GRINDING ONE OR MORE MINERAL MATERIALS CONSISTING OF AT LEAST ONE CALCIUM CARBONATE

摘要

A first object of the present invention is a process for dry grinding of one or more mineral materials which include at least one calcium carbonate, characterized in that the said process includes the stages of: a) crushing the mineral material or materials in at least one crushing unit until a crushed material is obtained with a d95 of less than 10 cm; b) possibly improving the material crushed according to stage a); c) dry grinding the material crushed according to stage a) and/or b) in at least one grinding unit: (i) in the presence of at least one comb-type hydrophilic polymer containing at least one polyalkylene oxide function grafted on to at least one unsaturated ethylene monomer, (ii) in such a manner that the quantity of liquid in the said grinding unit is less than 15% by dry weight of the said material crushed in the said crushing unit; d) possibly classifying the material dry ground according to stage c) with at least one classification unit; e) possibly repeating stages c) and/or d) on all or part of the dry ground material resulting from stages c) and/or d); and characterized in that the material recovered following stage c) and/or d) and/or e) has a d50 (average diameter) of 0.5 to 500 microns.